PROJECT SUMMARY Over 20 million women in the United States suffer from urinary incontinence, a condition associated with depression, social isolation, physical inactivity, falls and fractures, and loss of ability to live independently. Current first-line treatment for incontinence consists of behavioral strategies such as pelvic floor exercises that are difficult for most women to practice effectively when taught in course of routine care. Second-line treatments such as drugs or surgery have problematic side effects that make them inappropriate or unsafe for many women, particularly older women who are at greatest risk of incontinence. As a result, there is an urgent need for alternate treatment strategies that are not only effective, but also better tolerated. Yoga is a set of complementary physical and mental practices with the potential to improve incontinence through multiple mechanisms. When practiced in a way that emphasizes careful anatomic alignment, awareness of specific bodily structures, and mindful relaxation and deep breathing during the practice of physical yoga postures, yoga can be used to increase women's control over the pelvic floor muscles, improve peripheral autonomic function, and increase underlying physical function, all of which have the potential to improve bladder control. To explore the feasibility of using yoga as a behavioral management strategy for incontinence, our investigative team previously developed a structured, group-based yoga program involving twice weekly group classes supplemented by once weekly home yoga practice, in collaboration with an expert yoga panel. In a pilot trial involving ambulatory midlife and older women with at least daily incontinence, women assigned to this yoga intervention demonstrated an average ~74% decrease in frequency of any incontinence over 3 months. All but one woman assigned to yoga completed the program, adherence to group yoga classes over 3 months was greater than 90%, and no adverse events related to yoga were detected. We now propose to conduct a full-scale randomized trial to provide rigorous evidence of the efficacy of this yoga intervention for urinary incontinence in women aged 50 years and older. Women randomized to the yoga intervention will take part in twice-weekly group classes and once weekly home practice focused on study- specific yoga postures and techniques, while those randomized to the control intervention will engage in equivalent-time, non-specific muscle stretching classes and practice. In addition to assessing changes in incontinence, we will explore whether changes in pelvic floor strength, peripheral autonomic function, and lower extremity physical function as potential mediators of improvement in incontinence. If successful, this research has the potential to reduce the burden of one of the most common chronic conditions in midlife and older women, as well as provide new insights into factors influencing treatment response.